1. Field of the Invention
The present invention generally relates to a data transmission method, and in particular, to a control method of a storage apparatus providing different devices to access data concurrently.
2. Description of Related Art
Presently, mobile devices such as smart phones and tablet computers have become more prevalent. Such devices may not only provide versatile functionalities such as voice communication, text messaging, e-mail transmission, or web browsing by installing applications, but also provide photo shooting and video recording by using built-in cameras, which allow a user to record moments of daily life anytime and anywhere. Such devices may also serve as mini multimedia players providing the user to record, play, and share multimedia files such as photos and videos for entertainment purposes.
Flash memories with smaller sizes and less power consumption are used by the mobile devices as recording media of programs and files for portability and durability. Compared to the large storage capacity of conventional hard drives, the storage capacity of such memories may be relatively limited and expensive. Hence, memories with large storage capacity may not be configured in conventional mobile devices due to cost issues.
As the user install or store more applications and multimedia files in the devices, the limited storage space in the mobile devices may be insufficient. Hence, a wireless hard drive has been introduced on the market. It may not only provide a wired data connection and large storage capacity similar to a conventional mobile hard drive, but also include a wireless transmission feature, which may allow the mobile device to establish a wireless data connection for data transmission and expand the usable storage space for the mobile device accordingly.
However, the existing wireless hard drives may only perform data transmission by either a wireless connection approach or a wireless connection approach. When the user connects an external device to the wireless hard drive via a physical circuit such as a universal serial bus (USB), the wireless hard drive may establish a wired data connection with the external device for data transmission. When the user unplugs the external device from the wireless hard drive, the wireless hard drive may turn on a wireless transmission module to provide other devices to establish wireless data connections with it for data transmission. Hence, the wireless hard drive may only provide data access for one of the devices at one time. Once the hard drive is connected to and accessed by one of the devices, it may not be accessed by the other devices, and therefore the applicable range of the wireless hard drive is limited.